Electric-brtjsh holder



D. B. FLOWER.

ELECTRIC BRUSH HOLDER.

APPLICATION FILED JAN. 9. 1911.

1,319,147. Patented 001. 21,1919.

DAVID BURDESS FLOWER, OF GLENSIDE PENNSYLVANIA.

ELECTRIC-BRUSH HOLDER.

Specification of Letterslatent.

Patented Oct. 21, 1919.

Application filed January 9, 1917. Serial No. 141,480.

To all whom it may concern.-

-Be it known that I, DAVID BURDESS FLOWER, a citizen of the United States, re siding at Glenside, in the county of Montgomery and State of Pennsylvania, have invented a certain new and useful Improvement in Electric-Brush Holders, whereof the following is a specification, reference being had to the accompanying drawing.

My invention relates to means for adjustably supporting an electrical contact brush in cooperative relation with, and under pres sure, upon a rotary contact surface. As hereinafter described; my invention includes a holder which is merely a guide for a brush which'is movable therethrough but otherwise independent of said holder; the latter serving merely to precisely determine the position of such a brush. Such brushes are very costly and it is an object of my 1nvention to provide a holder which is adjustable to come as close as possible to the rotary contact surface with which the brush is to cooperate, so that as much as possible of the brush may be used before it is necessary to renew it. Moreover, the form of the invention shown in the drawing is so constructed and arranged that brushes ofdiiferent cross sectional area may be selectively used in connection therewith, and my invention is advantageous in that holders, of a given size and pattern, may be adjusted to cooperate with the brush supporting bars and rotary contact surfaces of electric machines of widely different sizes.

My invention includes the various novel features of construction and arrangement hereinafter more definitely specified.

In the drawing: Figure I is a front elevation of a holder embodying my. invention,

in connection with a cylindrical supporting bar which is part of the equipment of an electrical machine of the class contemplated.

Fig. II is a side elevation of said holder, showing the close relation of the same to the rotary contact surface.

Fig. III is a perspective view of the rotary adjustable stud by which spring pressure upon the brush guided by said holder may be precisely predetermined and varied.

Fig. IV is a front elevation of a brush box adapted to be adjustably connected with the holder shown in Figs. I'and II,but of a smaller size than the box shown in said figures.

Fig. V is a side elevation of a brush box adapted to be adjustably connected with the holder shown in FigsaI and II, but of a larger size than the box shown in said figures.

Fig. VI is a fragmentary side elevation of the split clamping hub of the holder frame shown in Figs. I and II: indicating how the same pattern and size of hub may be utilized for engagement with supporting bars of different sizes, without variation in the dimensions of the portion of said hub which is flexed as a hinge in the clamping operation of said hub.

In said figures; the brush 1, which is a rectangular block, is mounted to reciprocate in'the box 2 but is thrust toward the rotary contact surface 3 by the cylindriform cross head 4 of the lever 5- which is fulcrumed' upon the stud 6 and pressed in the direction of the arrow shown in Fig. II, by the coiled wire spring 7 which encircles said stud 6 between the bifurcations 8 of said lever. Said spring has its outer end 9 engaged with said lever and has its inner end 10 engaged in the slot 12 of said stud, as indicated in Figs. I and II. Said stud 6 is mounted for rotary adjustment in axially alined bearings in the bifurcations 13 and 14: of the holder frame 15 and has the circumferential series ofconical spot sockets 16 for selective engagement with the set screw 18 which is in screw threaded engagement with the bifurcation 14 of said frame 15 and has its inner conical end engaging one of said sockets 16, as indicated in Fig. II. Said stud is also rovided with a series of openings 20, pre erably extending diametrically therethrough, to receive a cross bar 21 by which said stud may be turned to adjust the tension of said spring 7 when said set screw 18 is retracted. However, it is to be understood that said stud may be provided with any other kind of a wrench hold. It is to be understood that said'cross bar 21, which is indicated in operative position in Fig. I, may be removed from said stud 6 when not required to turn the latter.

Said brush holder frame 15 is conveniently provided with the clamping hub 22 which is split at 23 and flexible at 24 sothat it may be rigidly clamped upon the supporting' bar 25 by bolts 26 which extend through lugs 27 on said frame and are engaged by nuts 28 as indicated in Fig. II. Of course, such connection permits of variation in the angular adjustment of said holder with reference to the axis of the contact surface 3. Moreover, it is to be noted that said lugs 27 form a housing protecting said lever 5 although affording space for its free Operation between them as indicated in Fig. I.

I am aware that it is not new to provide a brush holder with a clamping hub for engagement with a cylindrical supporting bar and permitting angular adjustment of the holder-with respect to the rotary contact surface for the brush. However, in all such devices of the prior art known to me, adjustment of the holder toward and away from such contact surface is necessarily accom panied by variation in the angular relation of the brush to the holder. On the contrary, in a holder constructed in accordance with my invention, the element of the holder which guides the brush may be adjusted toward and away from such contact surface without variation in the angular relation of the brush or of the holder frame which supports it.

Said holder frame 15 has the slot 30, shown in Fig. I, to receive the bolt stud 31 and the guide stud 32 of said brush box 2 and is conveniently made of such length as to permit adjustment of said box from the position shown in full lines in Fig. II, to the position shown in dotted lines in that figure. In other words, said slot 30 is coextensive with the range of adjustment of said box, which may be precisely adjusted to any position permitted by the length of said slot. It may be observed that said slot 30 is thus advantageously distinguished from a series of holes which necessitates a step by step adjustment. Said box may be secured in any desired position of adjustment with reference to said frame 15 by the nut 34: engaging said bolt stud 31 as indicated in Figs. I and II. I prefer to interpose a washer 35 between said nut 34: and the adjacent surface of the holder 15 to prevent marring the latter by the turning movement of said nut, and I also prefer to provide said bolt stud 31 with a cotter pin 37 to prevent accidental displacement of the parts when said nut 3a is loosened.

The boxes 39 and 40 shown respectively in Figs. IV and V are constructed and arranged like the box 2 shown in Figs. I and II, except that they are adapted to hold brushes of cross sectional area respectively different from that of said brush 1.

As the supporting bars 25 are of respectively different sizes in different electric machines; the single pattern and size of holder frame 15 shown in Figs. I and II is adapted for connection therewith by forming openings 41 and therein of respectively different sizes but preferably so located that the flexible portion 2% of the hub 22 remains of the same size, which is so proportioned as to permit of the clamping action above contemplated; said openings being more or less eccentrically disposed in said hub as indicated in Fig. VI.

As far as I am aware, the prior art does not include any electric brush holder comprising a frame with a brush guiding box movable thereon and thus capable of adjustment toward and away from the rotary contact surface, which is a characteristic feature of my device. Therefore, I do not desire to limit myself to the specific details of construction and arrangement of my invention herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention as defined in the appended claims.

I claim:

1. In an electric brush holder; the combination with a frame having a slot for engagement with a brush box, bifurcations with axially alined bearings, a hub with a cylindrical opening adapted to receive a supporting bar, and split for resilient engage ment with said bar; of clamping means for constricting said hub upon said bar; a stud mounted in said bearings, having a longitudinal slot, a circumferential series of spot sockets, and a wrench hold at one end thereof; a set screw in said frame arranged to selectively engage said sockets; a lever l1aving bifurcations, extending between the bifurcations of said. frame and ournaled upon said stud and arranged to press the brush; a coiled spring encircling said stud between the bifurcations of said lever, having one end engaging said lever and having the other end engaging the slot in said stud; a brush box adjustabl on said frame, toward and away from the contact surface with which the brush is to cooperatedizwing a bolt stud and a guide stud fitted to the slot in said frame; and a nut engaging the bolt stud on said box; whereby the latter may be secured in adjusted position.

2. In an electric brush holder; the combination with a frame having a slot for engagement with a brush box, bifurcations with axially alined bearings, a hub with a cylindrical opening adapted to receive a supporting bar, and split for resilient engagement with said bar; of clamping'means for con stricting said hub upon said bar; a stud mounted in said bearings, having a longitudinal slot, a circumferential series of spot sockets, and a Wrench hold at one end thereof; a set screw in said frame arranged to selectively engage said sockets, a lever having bifurcations journaled upon said stud and arranged to press the brush; a coiled spring encircling said stud, having one end engaging said lever and having the other end engaging the slot in said stud; a brush box adjustable on said frame, toward and away from the contact surface with which the brush is to cooperate, having a bolt stud and a guide stud fitted to the slot in said frame; and a nut engaging the bolt stud on said box; whereby the latter may be secured in adjusted position.

3. In an electric brush holder; the combination with a frame having a slot for engagement with a brush box, bifurcations with axially alined bearings, a hub with a cylindrical opening adapted to receive a supporting bar, and split for resilient engagement with said bar; of clamping means for constricting said hub upon said bar; a stud mounted in said bearings, having a circumferential series of spot sockets, and a wrench hold; means on said frame arranged to selectively engage said sockets; a lever journaled upon said stud and arranged to press the brush; a coiled spring encircling said stud, having one end engaging said' lever and having the other end engaging said stud; a brush box adjustable on said frame, toward and away from the contact surface with which the brush is to cooperate, and having a bolt stud and a guide stud fitted to the slot in said frame; and a nut engaging the bolt stud on said box; whereby the latter may be secured in adjusted position.

4. In an electric brush holder; the combination with a frame arranged for engagement with a brush box, having a bearing, and a hub adapted to receive a supporting bar; of means for securing said hub upon said bar; a stud mounted in said bearing, having a circumferential series of spot sockets, and a wrench hold; means on said frame arranged to selectively engage said sockets; a lever journaled upon said stud and arranged to engage the brush; a spring having one end engaging said lever and having the other end engaging said stud; a brush box adjustable on said frame, toward and away from the contact surface with which the brush is to cooperate; and means whereby said box may be secured in adjusted position on said frame.

5. In an electric brush holder, the combination with a frame having means for engagement with a separable brush box, including a single slot intermediate of the width of said frame; of a brush box adjustable on said frame, toward and away from the contact surface with which the brush is to cooperate; and means whereby said box may be secured in adjusted position on said frame, including a screw threaded bolt stud and an unthreaded guide stud rigidly connected with said box and both extending in said single slot, and a nut fitted to said bolt stud; whereby said single slot and said two studs in it limit both the digection and extent of adjustment of said ox. I

6. In an electric brush holder, the combination with a frame having a single slot; of a brush box adjustable on said frame; and means whereby said box may be secured in adjusted position on said frame, including two studs rigidly connected with said box in spaced relation, and extending in said single slot; whereby said single slot and said two studs in it limit both the direction and extent of adjustment of said box.

7. In an electric brush holder; the combination with a frame having a single slot; of a brush box adjustable on said frame; and means whereby said box may be secured in adjusted position on said frame, includ ing a bolt stud extending through said slot, and provided with a nut, exterior to said slot, and a guide stud shorter than said bolt stud and terminating in the same slot with said bolt stud.

8. In an electric brush holder, the combination with a frame having a single slot; of a brush box adjustable on said frame; and means whereby said box may be secured in adjusted position on said frame, including a slot in said frame coextensive with the range of adjustment of said box, and a smoothly cylindrical guide stud rigidly connected with said box and terminating in said slot.

In testimony whereof, I have hereunto signed my name at Philadelphia, Pennsylvania, this second day of January, 1917.

DAVID BURDESS FLOWER.

Witnesses:

F. A. ALTENEDEN, S. BINDER.

copies of this pltent may be obtained for flve cents each, by addressing the Commissioner of Patent. Washington, D. 0. 

